Insulin Structure & Function

Function
Insulin is located in the pancreas. It is made by the pancreatic islet cells. Insulin helps to regulate the blood glucose in the body. It converts the glucose into glycogen, storing it into the liver. The glycogen then converts the stored glycogen to glucose when the body is under fasting condition to provide energy. Insulin also helps to get rid of fatty acids. It slows the breakdown of triglycerides which leads to the reduction of fatty acids in the blood. When insulin is not able to produce from your body it causes your body to uses fatty acids for energy instead or carbohydrates.

Structure
Insulin is monomeric and is composed of two polypeptide chains. It is composed of two different types of peptide chains. Chain A has 21 amino acids and Chain B has 30 amino acids. Insulin has a three dimensional structure consisting of 3 helices and 3 conserved disulfide bridges. The molecules in insulin sometimes form dimers in solution due to the hydrogen bonding between the B chains. Granules consisting hexamers are also sometimes formed by insulin. This is caused by the intercation between hydrophobic surfaces.

Additional Resources
For additional information, see: Diabetes & Hypoglycemia